Type: enum
Default: TLSv1.2
Context: sighup
Restart: false
Values: [TLSv1, TLSv1.1, TLSv1.2, TLSv1.3]
Since: 12

Sets the minimum SSL/TLS protocol version to use. Valid values are currently: TLSv1, TLSv1.1, TLSv1.2, TLSv1.3. Older versions of the OpenSSL library do not support all values; an error will be raised if an unsupported setting is chosen. Protocol versions before TLS 1.0, namely SSL version 2 and 3, are always disabled.

The default is TLSv1.2, which satisfies industry best practices as of this writing.

This parameter can only be set in the postgresql.conf file or on the server command line.